my 350 keeps overheating at a idle. I have the perma coil 16in blade that says 2950 cfm with the aluminium shroud summit sells. aluminium radiator thats 26x19 and yes the shrouds covers all of the radiator. i have done the only test i can find about the fan being strong enough is if it will hold a 2x2in piece of cardboard on the outside of the radiator and yes it will hold it in place. I have flushed radiator and block with waterhose. i have tried 160 and 180 thermostats and also used 1 of the washers they sell. i just replaced the water pump with a new weiand(action plus) and still no improvement. the intial timing is set at 12 degrees.

the car will run cool(180-190) as long as ur running highway speeds. u get in traffic or just around town the car will be from 180 to 210 and rising in 10 to 15minutes. i just pull over when it gets over 220 and cut the car off.

does anyone have any ideas for me? any help would be appreciated.thanks

How fast are you driving your water pump?

7 3/4 crank and 6 3/4 water pulley

does any1 think if i put a pusher fan on the on the outside of the radiator that it will help any?

http://www.perma-cool.com/Catalog/CatImages/PG17-L2.gif

Does your fan look like this?

yes the 16in 2950 cfm. i also have the shroud summit sells

yes the 16in 2950 cfm. i also have the shroud summit sells

Your problem is strictly airflow production!!!!

Unfortunately, Permacool rates their fans with the "I feel like this number" scale! I have tested several of their fans and none have produced the claimed CFMS. These are particularily poor.

That fan I believe is about 10 amps continuous. Therefore...and this is a rule of thumb... even the best OEM, huge R&D bucked, fans will only produce between 100 and 110 CFMs per amp. Therefore.. do the arithmetic and it comes up a pretty lame ~1000cfms fan?

I would keep to either Spal or Derale... both of which do what they claim .... and are quality pieces. There are also a boatload of OEM fans out there from Volvos, to BMWs to Mustangs that have fantastic electric fans now. Check into these.

Steve is very right. your description of the problem alone very clearly shows that the fan is not moving enough air, tho the cooling system itself is adequate, and when the motion of the car is moving the air, it cools just fine.

would u go with a twin fan set up or just a single fan. have u ever had any experience with the flex-a-lite black magic xtreme cool thats suppose to have 3300 cfms. how many cfms does some1 need?
i bought a cheap pusher fan from o'reillys last nite that has like 1250cfm. would u try the pusher fan or not even waste ur time?

thanks 4 the help

Personally I'd go back to an engine driven mechanical fan and a full stock style shroud, but...

For electrics, I'd like a good dual fan setup, with a full shroud that holds the fan 2-3 inches behind the radiator, and a 2 step or variable electronic controller. 3000 cfm with both fans on max is barely enough, 5000 is certainly not too much.

I might lean more toward a factory setup salvaged from a boneyard, or a very high end aftermarket setup.

My Derale mechanical fan would blow the hood off the car if it wasn't bolted down, that's the kind of airflow you need.

If you have to have electric fans go with a Lincoln MK VII fan setup, or a Ford Taurus/Windstar setup, complete with their stock shrouds, which are actually part of the fans.

thanks 4 the help. i put a 7 blade mechanical fan on it. i drove the car for 40 minutes and the let it sit at idle for 20 min and it went to 200 and stayed there with a 160 thermostat. this was with the shroud i bought from summitt. so should i buy a factory shroud? or save the money and get a good elec fan and which fans r good 1?

I had a similar issue as you, and mine was resolved by installing a factory style shroud and setting the fan to the proper depth (half the fan in, half out of the shroud). I think you will find the consensus from guys here that the stock setup and shroud is very efficient and does an excellent job of cooling.

FWIW, 200* after driving the car for 40 minutes and letting idle for 20 minutes would not concern me. Sounds like you have already made an improvement over your initial post.

Jon

I haven't seen the summit shroud (link?) but I'd say if 200 is as high as it got, you've solved the problem. Possible additional improvements can be made, but 200 max after that kinda run ain't bad. I assume the temp stabilized at 200 for a period of time, or was it creeping up still?

If you have to have electric fans go with a Lincoln MK VII fan setup, or a Ford Taurus/Windstar setup, complete with their stock shrouds, which are actually part of the fans.
The Taurus/Lincoln electric fan will pull more than enough air to cool your setup but it will cost you an extra $90-$130 depending on the type of fan controller you use. I would not use any of the cheap controllers as they are not designed for the amperage the Taurus fan will pull when the fan starts. DC, Spal and Flexalite make some heavey duty controllers. Also will your alternator support the amp draw?

Or http://store.summitracing.com/partdetail.asp?autofilter=1&part=FLX%2D180&N=700+4294924500+4294839058+4294838842+400226+4294 891681+4294775280+4294792852+115&autoview=sku
but your looking at over $300.

Electric fans are great but the cheapest and easiest is still the manual set up.

my 350 keeps overheating at a idle. I have the perma coil 16in blade that says 2950 cfm with the aluminium shroud summit sells. aluminium radiator thats 26x19 and yes the shrouds covers all of the radiator. i have done the only test i can find about the fan being strong enough is if it will hold a 2x2in piece of cardboard on the outside of the radiator and yes it will hold it in place. I have flushed radiator and block with waterhose. i have tried 160 and 180 thermostats and also used 1 of the washers they sell. i just replaced the water pump with a new weiand(action plus) and still no improvement. the intial timing is set at 12 degrees.

the car will run cool(180-190) as long as ur running highway speeds. u get in traffic or just around town the car will be from 180 to 210 and rising in 10 to 15minutes. i just pull over when it gets over 220 and cut the car off.

does anyone have any ideas for me? any help would be appreciated.thanks

I just got my 69 running today. I am having the EXACT same problem. I have a new copper/brass radiator and I couldn't drive 2 miles without it heading toward 250 degrees...so get a bigger electric fan was the answer or should I change out the radiator..:confused::confused: